computer clicking and twitching tach

[c_k06]

ok when i start up the eclipse the computer starts ticking intermittently but erratically. when it does the tach twitches or drops 100 rpms or so, the lights flicker and the check engine light comes on. what is going on?????????
you can also hear a ticking sound under the hood closer to the coil pack area not sure exactly where tho..

 

[bryanwheat]

Your ecu is about to take a crap on you. The caps are leaking on the board causing it to only fire on 2 cylinders. This is very common. Hopefully you can get the capacitors replaced before there is any damage to the board.

 

[Dewayne Waldron]

The clicking your hearing near the ecu is the injector relay. That's the first thing that the capacitor's mess up when they leak. Capacitors are cheap and somewhat easy to install if you know what you are doing. Good Luck.

 

[steve]

The clicking your hearing near the ecu is the injector relay. That's the first thing that the capacitor's mess up when they leak. Capacitors are cheap and somewhat easy to install if you know what you are doing. Good Luck.

There isn't an injector relay. It's the MPI relay that powers the ECU and half of the engine bay. Your correct that it clicking is a likely sign of capacitor leakage reaching it's final stage.

 

[BlackNtTalon]

Sounds like the good ol "click of death"!! If you do not want to repair your ECU yourself, check out Motoguy's Garage they sell quality ECU's for a reasonable price or they could repair yours as well.

 

[96eclipzGsT]

Dude check to make sure the wiring harness is plugged in good under the fuel rail. Mine came loose and the tach would jump like that and it would backfire pretty good.

 

[steve]

Dude check to make sure the wiring harness is plugged in good under the fuel rail. Mine came loose and the tach would jump like that and it would backfire pretty good.

That would be the power transistor connector.

 

[steve]

Sounds like the good ol "click of death"!! If you do not want to repair your ECU yourself ...

If it wants it repaired he could always send it to me too and be sure it was done right.

 

[c_k06]

i have another computer that i got when i bought the car. i might try and put that in it. also when im going down the highway when i start to make boost anytime after 70mph or so it will chug and if i keep giving it pedal it will do it even harder as in (it feels like th engine is ready to rip out of the engine bay). i can barely give it pedal and it will accelerate but not much. i just replaced the original plug wires so now i have to take it out on the highway again to see if thats what it was. thank you for the info it really helps.
how easy is it to fix the ecu??
also the other ecu i have for it is for a 91 talon will that do??

 

[steve]

i have another computer that i got when i bought the car. i might try and put that in it.

also when im going down the highway when i start to make boost anytime after 70mph or so it will chug and if i keep giving it pedal it will do it even harder as in (it feels like th engine is ready to rip out of the engine bay). i can barely give it pedal and it will accelerate but not much.

i just replaced the original plug wires so now i have to take it out on the highway again to see if thats what it was.

how easy is it to fix the ecu??
also the other ecu i have for it is for a 91 talon will that do??

The ECUs for 91 and 92 cars were the same for the same type car. So a Federal turbo 5-speed AWD car used MD166262 both years and the Federal turbo 5-speed FWD car the MD166260. If your ECU part numbers are the same between what's in the car and the other one you have then it is the same ECU regardless of which car it came out of. Within the 91-93 range any of the turbo ECUs will start the car but there are important differences between the manual/automatic and less so between the FWD/AWD versions that you need to consider when continuing to use a swap over having the right ECU.

If you have to ask how easy is it then it's not really something you should be considering. To avoid damaging the circuit board you need a good soldering iron to avoid overheating the copper and burning the glue holding it to the board. You need the right solder and flux and a vacuum sucker to draw the solder out of the holes once you've melted it or solder wick to do the same.

Since the leakage is corrosive, once the caps leak it begin to damage other parts of the ECU so just changing the capacitors may not fix the problem or may for a short time before the residual electrolyte eats through something critical. Many times the damage is microscopic and only noticeable by measuring or noting behavour and knowing how the circuits work.

If you have some soldering background you might be successful in changing the caps or you might damage the ECU creating additional work and costs to get it fixed. There are lots of people who have done it themselves and lots more that had to send them in after they damaged them or failed.

The other problem may or may not be related. You could be describing fuel cut which is pretty violent or high speed misfire which isn't or something else entirely.

You'll see people talk about boost leak testing all the time. If you haven't done one you should.

Spark plug wires and the spark plugs can cause all sorts of problems. What brand of wires and plugs did you get. What did you gap the plugs to?

 

[c_k06]

i just got napa plug wires and the plugs i gapped to the oem settings that are in my manual. so the other computer that i have wont work?

 

[steve]

Did you get NGK spark plugs?

There are many different 91 Talons. What's the part number off the ECU?

 

[c_k06]

yes they are ngk plugs ngk iridium spark plugs
i will post the number tonight when i get it back from a friend

 

[steve]

In the future you want the basic copper plug NGK BPR6ES. They cost about $2 each.
People have mixed results with the iridium plugs and boost. Since changing the plugs on our cars is so easy the longer life of the iridium plugs is a unneeded expense and the fine tips may get too hot in our cars.

 

[c_k06]

ok my computer has
MD166255
E2T36572
2325 M

Is the M for manual transmission? i will install it today but hopefully i will get a reply by then... my friend just had it in his talon fwd turbo 5 speed and it did ok so as you said earlier that will be a minute difference... if i understood correctly.

 

[steve]

ok my computer has
MD166255
E2T36572
2325 M

Is the M for manual transmission? i will install it today but hopefully i will get a reply by then... my friend just had it in his talon fwd turbo 5 speed and it did ok so as you said earlier that will be a minute difference... if i understood correctly.

That's a ECU for a non-turbo car. It is programmed for 240cc injectors and doesn't have the board for your knock sensor or drivers for 3 of the solenoids used on a turbo car. The M doesn't mean manual, that same ECU was used in both automatic and manual 2.0L NA cars.

It will start the car but it will run poorly and burn twice as much fuel as it should.
There is a small difference between the MD166262 turbo AWD and the MD166260 turbo FWD ECUs but a huge difference between them and what you have.

 

[c_k06]

i installed it and it runs fine. it runs better than it ever has since ive had it anyways...
you all were dead on about the leaking capacitors tho electrolyte is all over the board haha i really appreciate it i love this website

 

[steve]

Well maybe someone put a turbo board inside the non-turbo case.
If it is a NA ECU and you think the car runs good you'll be really happy with how it runs using the right ECU.

 

[matt90gst]

listen to the ecu god! he knows his s#!T! he brought my ecu back from the DEAD. I highly recomend his services!

 

[c_k06]

i plan on getting the right ecu this is just a bandaid because im a little low on cash at the moment. how much would it cost me to have my old ecu fixed/replaced??

 

[steve]

Haha, I think we are all a little low on funds right now.

It can cost up to $150 to repair a ECU. All depends on how much work yours needs.
You might find a ECU cheaper in the classifieds but then there is the risk factor that what you get may need to be repaired anyway, either now or in a few months.

 

[c_k06]

true well like an eight of the board was covered n a lot of things were too